American Sign Language (ASL) is the primary means of communication for members of the Deaf community in the United States and parts of Canada. ASL is a natural language with its own syntax, phonology, and morphological structure. Not being a spoken language, ASL uses movements of the hands, and body and facial expressions to convey linguistic information. The study of prosody in American Sign Language provides an opportunity to gain an understanding of intonation, rhythmic phrasing, and linguistic timing as they translate into the manual modality. The proposed work aims to contribute to the structural understanding of ASL prosody by: (a) describing its intonation and rhythmic structure, (b) comparing it with signed English, which is not a natural language, to determine which characteristics of rhythm and timing are language- or modality- dependent, (c) evaluating the applicability of the task-dynamic model to ASL in an attempt to describe underlying control mechanisms of its production, and (d) investigating entrainment in simultaneous speaking and signing as a contributor to production difficulties. The proposed experiments will utilize an on-line recording technique (WATSMART) to record the location of small infrared light emitting diodes (IREDs) placed on the index finger, web of the hand, and thumb of each hand and on each wrist and elbow. Signing will also be videorecorded with and without IREDs. Linguistic and kinematic analysis over a range of stimulus complexity will provide a description of production characteristics, which will be confirmed perceptually through studies using a tapping paradigm.